package com.zenithmind.version.service.impl;

import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.zenithmind.common.context.UserContext;
import com.zenithmind.version.mapper.MergeRequestMapper;
import com.zenithmind.version.pojo.domain.MergeRequest;
import com.zenithmind.version.pojo.dto.MergeRequestCreateDTO;
import com.zenithmind.version.pojo.dto.MergeRequestUpdateDTO;
import com.zenithmind.version.pojo.query.MergeRequestQueryDTO;
import com.zenithmind.version.pojo.vo.MergeRequestVO;
import com.zenithmind.version.service.MergeRequestService;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.time.LocalDateTime;
import java.util.List;

/**
 * 合并请求服务实现类
 * 
 * @author ZenithMind Team
 * @since 2025-01-09
 */
@Slf4j
@Service
@RequiredArgsConstructor
public class MergeRequestServiceImpl extends ServiceImpl<MergeRequestMapper, MergeRequest> implements MergeRequestService {

    @Override
    @Transactional(rollbackFor = Exception.class)
    public MergeRequestVO createMergeRequest(MergeRequestCreateDTO createDTO) {
        log.info("创建合并请求: {}", createDTO.getTitle());
        
        // 检查合并冲突
        Object conflicts = checkMergeConflicts(createDTO.getRepositoryId(), createDTO.getSourceBranch(), createDTO.getTargetBranch());
        
        MergeRequest mergeRequest = new MergeRequest();
        BeanUtils.copyProperties(createDTO, mergeRequest);
        mergeRequest.setCreatorId(UserContext.getUserId());
        mergeRequest.setStatus(1); // 1: 开放状态
        mergeRequest.setCreateTime(LocalDateTime.now());
        mergeRequest.setUpdateTime(LocalDateTime.now());
        
        save(mergeRequest);
        
        // 添加审核者
        if (createDTO.getReviewerIds() != null && !createDTO.getReviewerIds().isEmpty()) {
            for (String reviewerId : createDTO.getReviewerIds()) {
                addReviewer(mergeRequest.getId(), reviewerId, UserContext.getUserId());
            }
        }
        
        return convertToVO(mergeRequest);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean updateMergeRequest(String id, MergeRequestUpdateDTO updateDTO) {
        log.info("更新合并请求: {}", id);
        
        MergeRequest mergeRequest = getById(id);
        if (mergeRequest == null) {
            throw new RuntimeException("合并请求不存在");
        }
        
        BeanUtils.copyProperties(updateDTO, mergeRequest);
        mergeRequest.setUpdateTime(LocalDateTime.now());
        
        return updateById(mergeRequest);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean deleteMergeRequest(String id) {
        log.info("删除合并请求: {}", id);
        
        MergeRequest mergeRequest = getById(id);
        if (mergeRequest == null) {
            throw new RuntimeException("合并请求不存在");
        }
        
        mergeRequest.setIsDeleted(1);
        mergeRequest.setUpdateTime(LocalDateTime.now());
        
        return updateById(mergeRequest);
    }

    @Override
    public IPage<MergeRequestVO> getMergeRequestPage(MergeRequestQueryDTO queryDTO) {
        log.info("分页查询合并请求");
        
        Page<MergeRequestVO> page = queryDTO.toPage();
        
        return baseMapper.selectMergeRequestPageWithDetails(
                page,
                queryDTO.getRepositoryId(),
                queryDTO.getStatus(),
                queryDTO.getAuthorId(),
                queryDTO.getAssigneeId()
        );
    }

    @Override
    public MergeRequestVO getMergeRequestDetail(String id) {
        log.info("获取合并请求详情: {}", id);
        
        return baseMapper.selectMergeRequestDetail(id);
    }

    @Override
    public List<MergeRequestVO> getRepositoryMergeRequests(String repositoryId, Integer status, Integer limit) {
        log.info("获取仓库的合并请求列表: repositoryId={}, status={}", repositoryId, status);
        
        return baseMapper.selectRepositoryMergeRequests(repositoryId, status, limit);
    }

    @Override
    public List<MergeRequestVO> getUserMergeRequests(String authorId, Integer status, Integer limit) {
        log.info("获取用户创建的合并请求: authorId={}, status={}", authorId, status);
        
        return baseMapper.selectUserMergeRequests(authorId, status, limit);
    }

    @Override
    public List<MergeRequestVO> getAssignedMergeRequests(String assigneeId, Integer status, Integer limit) {
        log.info("获取指派给用户的合并请求: assigneeId={}, status={}", assigneeId, status);
        
        return baseMapper.selectAssignedMergeRequests(assigneeId, status, limit);
    }

    @Override
    public Object checkMergeConflicts(String repositoryId, String sourceBranch, String targetBranch) {
        log.info("检查合并冲突: repositoryId={}, sourceBranch={}, targetBranch={}", repositoryId, sourceBranch, targetBranch);
        
        return baseMapper.checkMergeConflicts(repositoryId, sourceBranch, targetBranch);
    }

    @Override
    public List<Object> getMergeRequestChanges(String mergeRequestId) {
        log.info("获取合并请求的文件变更: mergeRequestId={}", mergeRequestId);
        
        return baseMapper.selectMergeRequestChanges(mergeRequestId);
    }

    @Override
    public List<Object> getMergeRequestCommits(String mergeRequestId) {
        log.info("获取合并请求的提交列表: mergeRequestId={}", mergeRequestId);
        
        return baseMapper.selectMergeRequestCommits(mergeRequestId);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Object executeMerge(String mergeRequestId, String userId) {
        log.info("执行合并: mergeRequestId={}, userId={}", mergeRequestId, userId);
        
        MergeRequest mergeRequest = getById(mergeRequestId);
        if (mergeRequest == null) {
            throw new RuntimeException("合并请求不存在");
        }
        
        if (mergeRequest.getStatus() != 1) {
            throw new RuntimeException("合并请求状态不允许合并");
        }
        
        // 检查是否可以自动合并
        if (!canAutoMerge(mergeRequestId)) {
            throw new RuntimeException("存在合并冲突，无法自动合并");
        }
        
        // TODO: 实现实际的合并逻辑
        String mergeCommitId = "generated_merge_commit_id";
        
        baseMapper.executeMerge(mergeRequestId, mergeCommitId, userId);
        
        return "合并成功";
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean closeMergeRequest(String mergeRequestId, String userId, String reason) {
        log.info("关闭合并请求: mergeRequestId={}, userId={}, reason={}", mergeRequestId, userId, reason);
        
        return baseMapper.closeMergeRequest(mergeRequestId, userId, reason) > 0;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean reopenMergeRequest(String mergeRequestId, String userId) {
        log.info("重新打开合并请求: mergeRequestId={}, userId={}", mergeRequestId, userId);
        
        return baseMapper.reopenMergeRequest(mergeRequestId, userId) > 0;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean addReviewer(String mergeRequestId, String reviewerId, String userId) {
        log.info("添加审核者: mergeRequestId={}, reviewerId={}, userId={}", mergeRequestId, reviewerId, userId);
        
        return baseMapper.addReviewer(mergeRequestId, reviewerId, userId) > 0;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean removeReviewer(String mergeRequestId, String reviewerId) {
        log.info("移除审核者: mergeRequestId={}, reviewerId={}", mergeRequestId, reviewerId);
        
        return baseMapper.removeReviewer(mergeRequestId, reviewerId) > 0;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean submitReview(String mergeRequestId, String userId, Integer status, String comment) {
        log.info("提交审核意见: mergeRequestId={}, userId={}, status={}", mergeRequestId, userId, status);
        
        return baseMapper.submitReview(mergeRequestId, userId, status, comment) > 0;
    }

    @Override
    public List<Object> getMergeRequestReviews(String mergeRequestId) {
        log.info("获取合并请求的审核记录: mergeRequestId={}", mergeRequestId);
        
        return baseMapper.selectMergeRequestReviews(mergeRequestId);
    }

    @Override
    public List<MergeRequestVO> searchMergeRequests(String keyword, String repositoryId, Integer status, Integer limit) {
        log.info("搜索合并请求: keyword={}, repositoryId={}, status={}", keyword, repositoryId, status);
        
        return baseMapper.searchMergeRequests(keyword, repositoryId, status, limit);
    }

    @Override
    public Object getMergeRequestStatistics(String repositoryId) {
        log.info("获取合并请求统计: repositoryId={}", repositoryId);
        
        return baseMapper.selectMergeRequestStatistics(repositoryId);
    }

    @Override
    public Object getUserMergeRequestStatistics(String userId) {
        log.info("获取用户合并请求统计: userId={}", userId);
        
        return baseMapper.selectUserMergeRequestStatistics(userId);
    }

    @Override
    public Boolean canAutoMerge(String mergeRequestId) {
        log.info("自动合并检查: mergeRequestId={}", mergeRequestId);
        
        MergeRequest mergeRequest = getById(mergeRequestId);
        if (mergeRequest == null) {
            return false;
        }
        
        // 检查合并冲突
        Object conflicts = checkMergeConflicts(mergeRequest.getRepositoryId(), mergeRequest.getSourceBranchName(), mergeRequest.getTargetBranchName());
        
        return conflicts == null;
    }

    @Override
    public Object getMergePreview(String repositoryId, String sourceBranch, String targetBranch) {
        log.info("获取合并预览: repositoryId={}, sourceBranch={}, targetBranch={}", repositoryId, sourceBranch, targetBranch);
        
        // TODO: 实现合并预览逻辑
        return null;
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Object resolveMergeConflicts(String mergeRequestId, Object conflictResolutions, String userId) {
        log.info("解决合并冲突: mergeRequestId={}, userId={}", mergeRequestId, userId);
        
        // TODO: 实现冲突解决逻辑
        return null;
    }

    /**
     * 转换为VO
     */
    private MergeRequestVO convertToVO(MergeRequest mergeRequest) {
        MergeRequestVO vo = new MergeRequestVO();
        BeanUtils.copyProperties(mergeRequest, vo);
        
        // TODO: 补充其他字段转换
        
        return vo;
    }
}
